Throughout this application, various articles and books are referenced by authorship and date. The full bibliographic citation for each publication can be found at the end of the specification, immediately preceding the claims.
It is well recognized that fungi produce antibiotics that are useful in the treatment of diseases, in industrial applications and as pesticides, e.g., penicillin, cephalosporins, tetracyclin, and cyclosporine, none of which are volatile. Many fungal species are known to emit low concentrations of gaseous substances, especially ones that have distinctive obnoxious odors, and this has prompted chemical analyses of the fungal volatiles (Bjurman et al., 1992). Some of these volatile substances are common to many fungi, whereas others seem to be unique for one species (Schnurer et al., 1999; Rapior et al., 2000). Dennis & Webster (1971) reported that certain Trichoderma spp. produced volatile antibiotics that inhibited the growth of such test fungi as Rhizoctonia solani, Pythium ultimum and Fusarium oxysporum. No lethality to any of the test fungi were reported by these authors and comprehensive chemical analyses of the volatile components of the fungal cultures was not performed, although acetaldehyde was suggested as one of the volatiles. Thus, in spite of some attention being given to the volatile compounds of fungal cultures over the years, no lethal mixture of volatile antimicrobials produced by fungi have been reported.
It is also well known that various microorganisms exhibit biological activity so as to be useful to control plant diseases. Although progress has been made in the field of identifying and developing biological pesticides for controlling various plant diseases of agronomic and horticultural importance, most of the pesticides in use are still synthetic compounds. Many of these chemical fungicides are classified as carcinogens by the EPA and are toxic to wildlife and other non-target species. For example, methyl bromide is widely used as a soil fumigant and to treat postharvest microbial infections. Due to its high toxicity to humans and animals and deleterious effect on the atmosphere, the use of methyl bromide will soon be eliminated and there is a great need to find safer replacements for this and other synthetic pesticides.
This invention satisfies this need and provides related advantages as well.